We really will need to see the particulars of claim (in full), and your defence in full, not just a summary.
The immediate thing that leaps out to me, from what we've seen so far, is your argument that you were just turning your vehicle round, vs the alleged time on site. A judge may want to know why it took 5 minutes and 27 seconds to simply turn round.
UKPC use DCB Legal who do have a habit of discontinuing claims, but may carry on if they think they've a good chance, so we will need to see the documents I referred to above.